510 Ohm Resistors?

[Grimzors]

Would the 510 ohm resistors that came with my blue LED's be ok to use? 1/w 10 led's power sourec 9v. thanks

[Grimzors]

Ok, 30 views and no replies? wth...

[Setch]

Maybe nobody understands your question. Maybe you need to provide more information. Maybe, just maybe, asking a question on a forum isn't the fastest way top get the information you need.

Maybe.

[Robert_the_damned]

Try using the search function on the forum. This topic has been covered many many times. Also I'm sure if you put 'led wiring' or something similar into google or any other search engine you'd find the exact information you need.

If you wire them in parrallel you will need something like a 33ohm resistor. A 9V battery wont drive 10 LED's in series though however.

[Grimzors]

Hmm well there is no store withing a 30 mile radius of me that sell's 150 ohm 1/4 resistors , radioshack can suck it. well now im still getting the same problem i did with the 510 ohm 1/4 watt resistors, the battery is heating up, but now it isnt as quickly, is that something i should worry about? any suggestions please help me :-/

[Setch]

Dude.... more information!

People know you have a battery, some LEDs and some resistors - how about explaining how you have it wired now?!

[Prostheta]

Okay. You need the forward voltage of the LEDs. You also need the average current recommended for them.

R=V/I

Ohm's Law.

R is your resistance value in Ohms.

Voltage is your battery voltage minus your forward voltage.

I is the current.

That is all.

[Grimzors]

OK, i have blue LED's 3.3 forward diode voltage or w/e its called, 20 mA, my resistors are now 100 ohms 1/4watt as the LED wizard told me to use 150 ohm 1/4 watt, i could not find 150 anywhere. is that a bit better? my dad says it might be the wire, i think its the wrong kind, the core is like bronze not silver..

[JTech]

you can go here it will tell you exactly how to wire your led's. as for the resistor you can check Radioshack

buy that pack of 500 resistors and have plenty for other projects. that pack has the resistor you need (150 ohms)

now i didn't understand when you said "radioshack can suck it"what did you mean?Too far

or did they not have this pack which contains plenty of 150 ohm resistors. well i hope this helped a little.

[Grimzors]

you can go here it will tell you exactly how to wire your led's. as for the resistor you can check Radioshack

buy that pack of 500 resistors and have plenty for other projects. that pack has the resistor you need (150 ohms)

now i didn't understand when you said "radioshack can suck it"what did you mean?Too far

or did they not have this pack which contains plenty of 150 ohm resistors. well i hope this helped a little.

Well in the pack of the resistors it does not say what kind they have, it onyl says its a multi pack of 1/4 resistors and im not about to spend $11 on a pack that im unsure of..lol

Should i use cable with the silver colored core instead of bronze? because my dad said the bronze cable might work to hard to heat up and get the current to LED's, thus making the battery get warm hot quicker, thanks

[Prostheta]

Do you know what resistors do, or how to use Google to find out what values they are? Trust me - that cable you have will be fine for small current applications. Unless that bronze stuff is toffee or something. Grab Google or Wikipedia and read up on how LEDs work, and why you need a resistor in series with them.

[Grimzors]

resistors work to keep the current controlled, i think? either way thats not the problem im having, the issue is the battery, im using the right resistors and LED's, thanks.

[Prostheta]

150 ohm is a quite low resistance and will let a lot of current flow through it. 60mA if I'm not mistaken. Given that you're dropping 3.3v, leaves 38mA. Hella loads! Can you post a link to the specs of the LEDs if you bought them online?

[Grimzors]

Description

Emitted Color : Blue

Size (mm) : 3mm

Lens Color : Water Clear

Peak Wave Length (nm) : 460 ~ 470

Forward Voltage (V) : 3.2 ~ 3.6

Reverse Current (uA) : <= 30

Luminous Intensity Typ Iv (mcd) : 4000(Typical) ~ 5000(Max)

Life Rating : 100,000 Hours

Viewing Angle : 20 Degree

Absolute Maximum Ratings ( Ta = 25°C )

Max Power Dissipation : 80 mw

Max Continuous Forward Current : 30 mA

Max Peak Forward Current : 75 mA

Reverse Voltage : 5 ~ 6 V

Lead Soldering Temperature : 240°C ( < 5 Sec )

Operating Temperature Range : -25°C ~ +85°C

Preservative Temperature Range : -30°C ~ +100°C

Quantity : 100

Free Resistors (Work for 12v)

is that better? lol

[Prostheta]

Okay, we'll use Ohm's Law here.

R=V/I

R is resistance, in kilohms.

V is voltage is volts.

I is current in milliamps.

Take you supply voltage and subtract your forward voltage in your specs.

V=9-3.3

V=5.7v

Therefore you have:

R=5.7/I

...where I is you maximum forward current...

R=5.7/30

R=0.19

This means to allow 30mA through your LED with 5.7v across it, you need a 0.19k resistor (190 Ohms). Given that you might not get a 190 Ohm resistor, take the next higher value (which will allow a little less current through, not more!) and you win.

Your closest E12 series resistor is 220 Ohms (allowing 25.9mA to flow), and your closest E24 series is 200 Ohms (allowing 28.5mA to flow).

Learn your math on this one and you'll be surprised how much you can start designing.

This is pretty good reference:

http://www.doctronics.co.uk/resistor.htm

[Grimzors]

Oh well, we are using the 100 ohm 1/4 watt already...i dont think ill be going back to chance the resistors...>_> we are already done with 4 LED's everything is going good the battery heats up, but i guess thats normal, the snag we are onto now is how to do the 12 fret marker with the 2 dots...lol ill keep you guys informed and remember to send me any info, as i will be making a tutorial, ive been taking pics here and there and have a few diagrams, i will give credit to those who contribute, thanks

[Prostheta]

Put two 100 Ohm resistors in series (in a chain) to make a 200 Ohm resistor :-D

I would recommend low-current LEDs myself, as you'll drain a battery pretty sharpish at that current!!

Edited December 12, 2006 by Prostheta

[Grimzors]

Yea thats smart but its too late! lol the battery is fine hasnt heated up only thing i am worried about now is the LED sticking out of the frethole, could i sand it down a bit? and i think im probably going to fill the hole with clear epoxy or something, i saw someone say that but yea also i hope it all fits down well, i asked my uncle for a dremmel so hopefully ill get one soon, here is a little demo pic of whats going to be in the tutorial http://i20.photobucket.com/albums/b237/Gri.../Picture177.jpg

[Prostheta]

I wouldn't be so hurried to write a tutorial if you're having problems perfecting the method man! Still, if you achieve it as a fully functional build as opposed to a board on the floor then cool.

I personally would have used side-facing LEDs and popped some frosted perspex in as rounded inlays as lenses. Anyway. Do go on.

[Grimzors]

Eh well maybe next time, and yea im planning on finishing the re attachment i think thats when i will post it up, just because i ran into some snags doesnt mean it came out wrong, ofcourse ill write down things i didnt do in advance etc, but thats for your help